TANDES MiIG Welding Residual Stress Analysis Of 7A52 Aluminum Alloy Based On SYSWELD

The application of 7A52 aluminum alloy, a kind of high-strength armor aluminum, is limited for its welding residual stress in welding components. Therefore, the research on residual stress of aluminum is rather important to expand the scope of application of aluminum. The finite element analysis methods used to simulate the residual stress of 7A52 aluminum alloy welding joint has great significance for mastering the residual stress distribution and improving joint performance of aluminum alloy on the basis of saving time and effort.The material database of 7A52 aluminum alloy was initially established by consulting literature and using Jmatpro software to get parts of thermal physical parameters of 7A52 aluminum alloy. Two double ellipsoid heat source models were established and checked by using the characteristics of SYSWELD itself taking into account of the heat load phenomenon and welding characteristics of TANDEM welding. The TANDEM welding feature of two heat sources successively loading onto the weld and "double source" was achieved by setting the loading time difference, which was flexible and without programming. Furthermore, it can be extended to a multi-wire welding heat source model.The welding temperature field and residual stress field of 7A52 aluminum alloy butt joints MIG welding of weld joint were simulated using the finite element SYSWELD and its pre-processing environment Visual-Environment for the difficulty of establishing TANDEM welding heat source model and limitation of 7A52 aluminum alloy for the existence of residual stress. The temperature field results show that it produced the phenomena of rapid heating and cooling at the start and end of welding process due to the different loading welding time of two heat sources. The residual stress field results show that the longitudinal residual stress vertical welding direction appear the typical "Twin Peaks" phenomenon and the transversal residual stress along welding direction were compressive stress at the both ends and tensile stress in the middle.The accuracy of the simulation results was confirmed the reliability of heat source model built was verified using of blind-hole methods to measure the welding residual stress vertical welding and alone welding direction. It will lay a good foundation for the further use of the software SYSWELD to analysis welding heat source model of multi-wire welding.